1. Technical Field
The disclosure relates to a capsule endoscope system that causes a capsule endoscope to be introduced into a subject and observes an inside of the subject.
2. Related Art
In the field of endoscopes, capsule endoscopes which can be introduced into a digestive tract of a subject such as a patient have been developed (for example, see Japanese Patent Application Laid-open No. 2009-213613, International Publication Pamphlet No. WO 2008/062594, and International Publication Pamphlet No. WO 2011/061968). The capsule endoscopes are devices having an imaging function and a wireless communication function inside a capsule-shaped casing. The capsule endoscopes sequentially image an inside of an organ of the subject to acquire image signals while moving inside the digestive tract by peristaltic movement after swallowed through a mouse of the subject, and wirelessly transmit the image signals to a receiving device outside the subject. The image signals received in the receiving device is taken into an image display device, and predetermined image processing is applied. Accordingly, an image inside the organ (may also referred to as in-vivo image) is displayed as a still image or a moving image. A user such as a doctor observes the in-vivo image displayed on an image display device as described above, and diagnoses a state of the organ of the subject.
In recent years, systems having a function to guide a capsule endoscope introduced into a subject by magnetic force (hereinafter, referred to as magnetic guidance) has been proposed. For example, Japanese Patent Application Laid-open No. 2009-213613 discloses a capsule guidance system in which a permanent magnet (hereinafter, may also referred to as in-vivo permanent magnet) is provided inside the capsule endoscope, and a magnetic guidance device including a magnetic field generating unit is installed outside the subject, and which guides the capsule endoscope into a position desired by the user by causing a magnetic field formed by the magnetic field generating unit to act on the in-vivo permanent magnet. In such a system, the user can magnetically guide the capsule endoscope into a desired position and direction by operating an operating unit provided in the magnetic guidance device to change the magnetic field while referring to an in-vivo image displayed on the image display device.
Further, a capsule endoscope that has a liquid such as water introduced into a stomach of the subject, and images an inside of the stomach in a state where the capsule endoscope floats in the liquid is also known. For example, International Publication Pamphlet No. WO 2008/062594 discloses a capsule endoscope configured to stand in a state of floating in a liquid (an imaging direction becomes a vertical direction), and which can image upper and lower portions of a liquid surface.
Further, when operating an endoscope introduced into a subject, it is important to grasp which body part in the subject from which direction the capsule endoscope is currently observing. As a technology for grasping body parts for observation, for example, Japanese Patent Application Laid-open No. 60-217326 discloses a technology for displaying an endoscope graphic and an observation position mark together with a side surface image and a developed image of a stomach. Japanese Patent Application Laid-open No. 2003-225195 discloses a technology for displaying a shape of an organ, which is an object into which an inserting unit of a flexible endoscope is inserted, together with a bent state of the inserting unit. Japanese Patent Application Laid-open No. 2007-319327 discloses a technology for recording a gaze of the user (observer) and an operation record of a GUI in time series, and identifying an observed region by the user from the records, in observation work. Japanese Patent Application Laid-open No. 2004-321796 discloses a technology for recording an in-vivo image, and a position and a direction of the capsule endoscope at the time of imaging the in-vivo image, and displaying a pseudo three-dimensional display of a surrounding region of the capsule endoscope based on the aforementioned records.